linux-bl808/fs
Mathieu Desnoyers a961e40917 membarrier: Provide register expedited private command
This introduces a "register private expedited" membarrier command which
allows eventual removal of important memory barrier constraints on the
scheduler fast-paths. It changes how the "private expedited" membarrier
command (new to 4.14) is used from user-space.

This new command allows processes to register their intent to use the
private expedited command.  This affects how the expedited private
command introduced in 4.14-rc is meant to be used, and should be merged
before 4.14 final.

Processes are now required to register before using
MEMBARRIER_CMD_PRIVATE_EXPEDITED, otherwise that command returns EPERM.

This fixes a problem that arose when designing requested extensions to
sys_membarrier() to allow JITs to efficiently flush old code from
instruction caches.  Several potential algorithms are much less painful
if the user register intent to use this functionality early on, for
example, before the process spawns the second thread.  Registering at
this time removes the need to interrupt each and every thread in that
process at the first expedited sys_membarrier() system call.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-19 22:13:40 -04:00
..
9p 9p: set page uptodate when required in write_end() 2017-10-11 09:30:08 -07:00
adfs
affs
afs
autofs4
befs
bfs
btrfs Merge branch 'for-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux 2017-10-06 09:03:08 -07:00
cachefiles
ceph ceph: fix __choose_mds() for LSSNAP request 2017-10-02 16:18:16 +02:00
cifs SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags 2017-09-22 19:47:17 -05:00
coda
configfs
cramfs
crypto
debugfs
devpts
dlm
ecryptfs
efivarfs
efs
exofs
exportfs
ext2
ext4
f2fs f2fs: fix potential panic during fstrim 2017-10-03 08:06:05 -07:00
fat
freevxfs
fscache
fuse
gfs2 GFS2: Fix an old regression in GFS2's debugfs interface 2017-09-25 15:41:56 -07:00
hfs
hfsplus
hostfs
hpfs
hugetlbfs
isofs isofs: fix build regression 2017-09-18 12:24:26 +02:00
jbd2
jffs2
jfs
kernfs
lockd
minix
ncpfs
nfs NFSv4/pnfs: Fix an infinite layoutget loop 2017-10-04 14:06:54 -04:00
nfs_common
nfsd nfsd4: define nfsd4_secinfo_no_name_release() 2017-10-05 14:45:25 -04:00
nilfs2
nls
notify
ntfs
ocfs2
omfs
openpromfs
orangefs
overlayfs ovl: fix regression caused by exclusive upper/work dir protection 2017-10-05 15:53:18 +02:00
proc sched/debug: Add explicit TASK_PARKED printing 2017-09-29 11:02:57 +02:00
pstore
qnx4
qnx6
quota quota: Generate warnings for DQUOT_SPACE_NOFAIL allocations 2017-10-10 17:24:46 +02:00
ramfs
reiserfs
romfs
squashfs
sysfs
sysv
tracefs
ubifs
udf
ufs
xfs xfs: move two more RT specific functions into CONFIG_XFS_RT 2017-10-16 12:26:50 -07:00
aio.c
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf.c
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c fs/binfmt_misc.c: node could be NULL when evicting inode 2017-10-13 16:18:33 -07:00
binfmt_script.c exec: load_script: kill the onstack interp[BINPRM_BUF_SIZE] array 2017-10-03 17:54:25 -07:00
block_dev.c fs/mpage.c: fix mpage_writepage() for pages with buffers 2017-10-13 16:18:33 -07:00
buffer.c
char_dev.c
compat.c
compat_binfmt_elf.c
compat_ioctl.c
coredump.c
dax.c
dcache.c
dcookies.c
direct-io.c Changes since last update: 2017-10-18 14:51:50 -04:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c membarrier: Provide register expedited private command 2017-10-19 22:13:40 -04:00
fcntl.c fcntl: Don't set si_code to SI_SIGIO when sig == SIGPOLL 2017-09-18 22:51:14 -05:00
fhandle.c
file.c
file_table.c
filesystems.c
fs-writeback.c
fs_pin.c
fs_struct.c
inode.c
internal.h
ioctl.c
iomap.c fs: invalidate page cache after end_io() in dio completion 2017-10-16 12:11:56 -07:00
Kconfig
Kconfig.binfmt
libfs.c
locks.c
Makefile
mbcache.c
mount.h
mpage.c fs/mpage.c: fix mpage_writepage() for pages with buffers 2017-10-13 16:18:33 -07:00
namei.c
namespace.c ovl: fix may_write_real() for overlayfs directories 2017-10-05 15:53:18 +02:00
no-block.c
nsfs.c
open.c
pipe.c
pnode.c
pnode.h
posix_acl.c
proc_namespace.c
read_write.c vfs: Return -ENXIO for negative SEEK_HOLE / SEEK_DATA offsets 2017-09-26 13:46:06 -07:00
readdir.c
select.c
seq_file.c
signalfd.c
splice.c
stack.c
stat.c
statfs.c
super.c
sync.c
timerfd.c
userfaultfd.c userfaultfd: non-cooperative: fix fork use after free 2017-10-03 17:54:25 -07:00
utimes.c
xattr.c lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-04 18:03:15 +11:00